(In reply to comment #1)
> I admit I don't have the first clue how to replay that trace. Can you give me
> some pointers?
Sure. Please do:
git clone https://github.com/apitrace/apitrace.git
cd apitrace
cmake .
make
wget http://people.freedesktop.org/~jrfonseca/traces/topogun-1.06-orc-84k.trace
./glretrace topogun-1.06-orc-84k.trace
This should reproduce the issue -- the humanoid's face is mostly dark with some bogus coloring instead of shaded grey. I can get a screenshot when I get home.
You can find some more background info about apitrace's tools on the README. In particular there's a GUI which might be useful for you to pinpoint the problem.